The Sailor Pen Co., Ltd.

Koichi Murakawa

Koji Matsuo

Shinko Mukoda

Akane Nishio

There are provided an aqueous ballpoint pen refill which can produce tasteful writings or drawings with a plurality of colors and which gives an attractive impression, since the inks in the ink reservoir constitute an interesting pattern and also a process for producing the same. A plurality of aqueous inks Ia and Ib with different colors are charged into an ink reservoir having a point tip at the front end to form a vertical or horizontal layered structure or a spiral structure; the aqueous inks containing pigments as coloring agents respectively and each having a viscosity of 45 mPa.multidot.S or more; the specific gravity difference of the inks being not more than 0.05. Injection needles connected respectively to front ends of a plurality of ink tanks are inserted to the transparent ink reservoir, and the plurality of inks with different colors are injected while the injection needles are drawn out of the ink reservoir.

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Tokyo, Japan

Koichi Murakawa